| 摘要 |
<p>Apparatus is disclosed which modifies a video signal (in the video frequency range) for scrambling (encoding) and unscrambling (decoding) video signals for television pictures by inverting selected lines in one field of a frame and by transmitting the corresponding lines in the other field of the frame not inverted. The lines transmitted not inverted in the one field are transmitted inverted in the other field. Decoding is accomplished by the reverse process, namely by reinverting the inverted lines in both fields of a frame.</p> |
